a little more information would help me better understand a specific sentence about layout

[Enter feedback here]
"In a VerticalStackLayout, child views expand to fill the available width when their size isn't explicitly set."
The next example uses Labels with no explicit widthrequest. I would like a bit explanation or a more precise wording as I expect the Labels to fill the available space if no widthrequest is specified.

Also the previous example uses Rectangles with explicit widthrequests set to 300 and they seem to fill the space horizontally. The sentence above tells me that this setting is unnecessary.

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#### Document Details

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* ID: 3e6ac280-657f-50f4-b6a5-2ca886e96bcc
* Version Independent ID: 3e6ac280-657f-50f4-b6a5-2ca886e96bcc
* Content: [VerticalStackLayout - .NET MAUI](https://docs.microsoft.com/en-us/dotnet/maui/user-interface/layouts/verticalstacklayout)
* Content Source: [docs/user-interface/layouts/verticalstacklayout.md](https://github.com/dotnet/docs-maui/blob/main/docs/user-interface/layouts/verticalstacklayout.md)
* Product: **dotnet-mobile**
* Technology: **dotnet-maui**
* GitHub Login: @davidbritch
* Microsoft Alias: **dabritch**